function Set() {
    this.elements = new Array();
    //获取Set元素个数
    this.size = function() {
        return this.elements.length;
    }

    //判断Set是否为空
    this.isEmpty = function() {
        return (this.elements.length < 1);
    }

    //清除Set
    this.clear = function() {
        this.elements = new Array();
    }
    //增加一个元素，不重复
    this.add = function(value) {
        //alert(this.containsKey(_key));
        if(this.containsValue(value)){
            this.remove(value);
        }
        this.elements.push(value);
    }
    //移除一个值
    this.remove = function(value) {
        var bln = false;
        try {

            for (i = 0; i < this.elements.length; i++) {

                if (this.elements[i] == value) {

                    this.elements.splice(i, 1);

                    return true;
                }
            }
        } catch (e) {
            bln = false;
        }
        return bln;
    }

    //移除一个值,索引
    this.kill=function (index){
        this.remove(this.get(index));
    }

    //得到一个值,索引
    this.get = function(_index) {
        if (_index < 0 || _index >= this.elements.length) {
            return null;
        }
        return this.elements[_index];
    }

    //查看是否包含一个值
    this.containsValue = function(value) {
        var bln = false;
        try {
            for (i = 0; i < this.elements.length; i++) {
                if (this.elements[i] == value) {
                    bln = true;
                }
            }
        } catch (e) {
            bln = false;
        }
        return bln;
    }
}
